It feels to me like array.concat seems slower than the equivalent (I 
think) variation using array.push:

>> a = [1,2,3,4,5]; b=[]; puts Benchmark.measure{ (1..100000).each{ b.push(*a)}}
   0.090000   0.000000   0.090000 (  0.090436)

>> a = [1,2,3,4,5]; b=[]; puts Benchmark.measure{ (1..100000).each{ b.concat(a)}}
   0.290000   0.000000   0.290000 (  0.296501)

(using ruby 1.8.4)

This surprised me somewhat, because earlier
(http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/7521)
it was suggested that concat is a fast way of appending to arrays.


Is there something I'm missing, or does it seem I should be
using push(*a) in places where I had been using concat(a)?